It is proposed to develop an inexpensive, scalable, and reproducible photolithographic protein immobilization technology for the fabrication of biosensors and biochips, that will covalently attach proteins to a surface in a uniform orientation, and that will be highly suitable for miniaturization. The technology is based on a light-activated chemistry that will attach proteins to a novel matrix via highly stable covalent bonds. Due to the properties of the reaction, immobilized proteins will maintain their activity and specificity. The matrix will be prepared by attaching reactive groups by silylation. An oligopeptide affinity tag will be isolated from a phage display library that binds to the matrix with high affinity, specifically orientating the protein on the matrix, and forms a covalent bond with the matrix, upon light activation. Because of the immediate compatibility of the chemistry with conventional lithographic methods of chip printing, it will be possible very precisely to control the reaction and limit protein attachment to specific surfaces. Thereby, protein immobilization will become more reproducible, and miniaturization will be facilitated.